508 1.6 Vti Engine Failure Warning and Fan on

2011 Peugeot 508 1.6 vti semi-automatic vehicle (it's been 20 days) the seller did not report that there is such a problem, which is the following;

The vehicle is cold engine at first start, engine failure warns that the vehicle should be repaired, the engine warning lamp turns on and the fan turns on at full speed.

The vehicle is at different points. They connected obd and looked, but the oxygen sensor gives warnings such as rich fuel. As far as I understand, the problem is a chronic one.

However, I am looking for a master who can find the source of this problem. It is important that this master eats halal bites, I believe that there are masters who do not call a piece of three-lira work a three-hundred-lira piece.